Self-priming adapter apparatus and method

ABSTRACT

Some embodiments of the invention provide a self-priming adapter system including a pump inlet receiving liquid mixed with air, a pump coupled to the pump inlet, and a self-priming adapter coupled to the pump. The self-priming adapter includes a separation chamber. The separation chamber includes one or more baffles to substantially separate the air from the liquid. The self-priming adapter system also includes a recirculation line coupled to the self-priming adapter to return the liquid to the pump inlet. Some embodiments of the invention provide a self-priming adapter for use with existing pumps of any type. Some embodiments of the invention provide a method of self-priming a pump using a self-priming adapter.

RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 119 to U.S.Provisional Patent Application No. 60/841,295 filed on Aug. 30, 2007,the entire disclosure of which is incorporated herein by reference.

BACKGROUND

Centrifugal pumps are often used in agricultural sprayer systems to pumpliquid from a tank to a boom for distribution. Centrifugal pumps can besubject to air locks due to loss of prime. Self-priming pumps have beendesigned to attempt to increase the priming capabilities of centrifugalpumps. However, conventional self-priming pumps include complex andheavy castings that serve as the input manifold of the centrifugal pump.Also, conventional self-priming pumps generally must be mountedvertically, which limits the configurations in which the pump can beinstalled. In addition, conventional self-priming pumps generally lowerthe performance of the pump to below its standard performance level.

SUMMARY

Some embodiments of the invention provide a self-priming adapter systemincluding a pump inlet receiving liquid mixed with air, a pump coupledto the pump inlet, and a self-priming adapter coupled to the pump. Theself-priming adapter includes a separation chamber. The separationchamber includes one or more baffles to substantially separate the airfrom the liquid. The self-priming adapter system also includes arecirculation line coupled to the self-priming adapter to return theliquid to the pump inlet. Some embodiments of the invention provide aself-priming adapter for use with existing pumps of any type. Someembodiments of the invention provide a method of self-priming a pumpusing a self-priming adapter.

Other aspects of the invention will become apparent by consideration ofthe detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a self-priming adapter system accordingto one embodiment of the invention.

FIG. 2 is a side view of the self-priming adapter system of FIG. 1.

FIG. 3 is a perspective view of a self-priming adapter system accordingto another embodiment of the invention.

FIGS. 4A, 4B, and 4C are perspective, front, and side views of aseparation chamber for use with the self-priming adapter system of FIGS.1 and 2.

FIG. 5 is a perspective view of a self-priming adapter system accordingto another embodiment of the invention.

FIG. 6 is another perspective view of the self-priming adapter system ofFIG. 5.

FIG. 7 is a partial cross-sectional front view of the self-primingadapter system of FIGS. 5 and 6.

FIG. 8 is a partial cross-sectional perspective view of the self-primingadapter system of FIGS. 5 and 6.

FIG. 9 is a partial cross-sectional front view of a self-priming adaptersystem including a check valve.

FIGS. 10A, 10B, 10C, and 10D are perspective, top, cross-sectional side,side, and cross-sectional front views of a separation chamber accordingto one embodiment of the invention.

FIG. 11 is a front view of a separation chamber according to oneembodiment of the invention including baffles and anti-vortex screens.

FIG. 12 is a graph of priming times for a self-priming adapter havingtwo inch baffles according to one embodiment of the invention.

FIG. 13 is a graph of priming times for a self-priming adapter havinganti-vortex screens according to one embodiment of the invention.

FIG. 14 is a data table that includes test priming rate data.

FIG. 15 is a graph of a self-priming rate of a pump fitted with theself-priming adapter of FIG. 5.

FIG. 16 is a graph of flow, liquid pump pressure, and rotationalfrequency over time for a pump fitted with a self-priming adapter.

FIG. 17 is a graph of pump lift capacity data for several pump modelswith and without self-priming adapter systems according to someembodiments of the invention.

DETAILED DESCRIPTION

Before any embodiments of the invention are explained in detail, it isto be understood that the invention is not limited in its application tothe details of construction and the arrangement of components set forthin the following description or illustrated in the following drawings.The invention is capable of other embodiments and of being practiced orof being carried out in various ways. Also, it is to be understood thatthe phraseology and terminology used herein is for the purpose ofdescription and should not be regarded as limiting. The use of“including,” “comprising,” or “having” and variations thereof herein ismeant to encompass the items listed thereafter and equivalents thereofas well as additional items. Unless specified or limited otherwise, theterms “mounted,” “connected,” “supported,” and “coupled” and variationsthereof are used broadly and encompass both direct and indirectmountings, connections, supports, and couplings. Further, “connected”and “coupled” are not restricted to physical or mechanical connectionsor couplings.

FIGS. 1 and 2 illustrate a self-priming adapter system 10 according toone embodiment of the invention. The self-priming adapter system 10 caninclude a pump 12, a self-priming adapter 14, a pump outlet 16, arecirculation line 18, a pump inlet 20, and an air outlet 22. In someembodiments, the self-priming adapter system 10 can also include arecirculation valve 24, a pump outlet valve 26, a liquid tank inletvalve 28, a fill line valve 30, and a tank valve 32. In someembodiments, the self-priming adapter system 10 can also include a cleanliquid tank line 34, a boom outlet line 36, a tank line 38, a pumpoutlet line 40, a fill line 42, and a self-priming adapter inlet line44. In some embodiments, the self-priming adapter system 10 can includea number of connectors, such as T-fittings 46, 48, 50.

In some embodiments, the self-priming adapter system 10 can protect thepump 12 from a dry run condition. In some embodiments, an automatedsystem (not shown) can be used to prevent dry-run conditions, which aredetrimental to centrifugal pumps. In some embodiments, the self-primingadapter system 10 can be used with any centrifugal pump (such as an openor closed impeller centrifugal pump) to convert a standard pump to aself-priming pump 12. In some embodiments, the self-priming adaptersystem 10 can convert existing pumps to on-load sprayers. In someembodiments, the self-priming adapter system 10 can provide fastself-priming rates. The self-priming adapter 14 can be used with othersuitable types of pumps, not only centrifugal pumps.

The self-priming adapter system 10 can provide a path for liquid (e.g.,liquid) to circulate through the pump 12. The self-priming adapter 14can include a separation chamber 54 that can allow entrained air topercolate out of the liquid being circulated and can release air back tothe atmosphere. The liquid can return back to the pump inlet 20, inorder to evacuate air from the pump inlet 20. In some embodiments, theself-priming adapter 14 can provide fast self-priming capabilities toany closed impeller centrifugal pump.

When circulated liquid enters the impeller of the pump 12 with airpresent, the air can be entrained into the liquid, increasing itsvolume. The liquid can then be carried through the pump 12 to theseparation chamber 54. In some embodiments, the separator chamber 54 canhold enough volume of liquid to fill the cavity of the pump 12 and thepump inlet 20. When the pump 12 is restarted, liquid can circulatethrough the pump 12 and can be directed into the separator chamber 54,where the velocity of the liquid can be slowed to a point where airbubbles can percolate up to the top and out of the air outlet 22,thereby evacuating air from the pump inlet 20. In a properly-sizedseparation chamber 54, liquid flow can slow to the point where entrainedair can percolate upward and out toward the atmosphere. The liquid canbe pulled back toward the pump inlet 20, which may be at negativepressure. The separation chamber 54 can allow for recirculation ofpumping liquids so that the pump inlet 20 can be evacuated of air. Inother words, the separation chamber 54 is used to separate air bubblesfrom the liquid being circulated. In some embodiments, the self-primingadapter system 10 can be gravity fed to help avoid air locks in thelines.

Once all the air has been evacuated from the pump inlet 20 and the pump12 has been primed, the recirculation line 18 can be closed. Once therecirculation line 18 is closed, the pump 12 can operate according toits normal pumping operation. If the recirculation line 18 is notclosed, a large drop in performance output can occur.

By increasing the amount of liquid circulating through the self-primingadapter system 10, priming rates can be increased. Priming rates canrange from no priming with circulation flow less than three gallons perminute to one foot per second in a two inch hose with 40 gallons perminute of circulation flow (e.g., see FIG. 16). The size/volume of theseparator chamber 54 can be increased as the circulation flow increases.The size, shape, and position of the separator chamber 54 can be chosento properly fill the pump 12 at startup. Also, in some embodiments, thesize of a manifold of the pump 12 chosen for a particular applicationcan be minimized in order to minimize the amount of liquid necessary toinitiate priming and increase priming efficiency. In some embodiments,the self-priming adapter system 10 can allow for the pump 12 to bemounted in tight configurations. In some embodiments, variousorientations of the pump 12 can be applied and the self-priming adapter14 and its separator chamber 54 can be mounted some distance (e.g.,three meters) away from the pump 12 while continuing to provideself-priming capabilities. Also, the volute leading to the pump outlet16 can be rotated if desired for a particular configuration. Inaddition, the pump inlet 20 can be raised from the position that wouldbe necessary for a conventional self-priming pump.

Optimal characteristics and designs of the separation chamber 54 can bedeveloped, for example, using a formula for sizing the separationchambers 54 to meet pump 12 flow capacities. In some embodiments, as thepump 12 capacity increases, the amount of circulation flow required toachieve fast priming rates also increases. In some embodiments, the topof the separation chamber 54 can be mounted to be substantially levelwith a top portion of an impeller eye within the pump 12. In someembodiments, providing liquid to the pump inlet 20 at ten gallons perminute or more (e.g., liquid from a fresh liquid tank) can allow thepump to prime as well.

As shown in FIG. 2, in one embodiment, the maximum self-priming adapter14 height can be substantially no higher than the bottom of the fillport in the fill line valve 30. Also, the minimum self-priming adapter14 height can be substantially no lower than a top portion of the pumpinlet 20 (e.g., a top portion of a casting on the pump inlet 20). Insome embodiments, the maximum hose length between the pump 12 and theself-priming adapter 14 can be about three meters. In some embodiments,the air outlet 22 can have a minimum diameter of 25 mm. In someembodiments, the air outlet 22 can extend ½ meter above the self-primingadapter 14. However, in some embodiments, the air outlet 22 (or ventline) can be eliminated.

FIG. 3 illustrates another embodiment of a self-priming adapter system10, including a pump 12, a self-priming adapter 14, a recirculation line18, a vent line 22, a clean liquid tank line 34, a boom outlet line 36,a tank line 38, a fill line 42, and a self-priming adapter inlet line44. In some embodiments, as shown in FIG. 3, “Y” fittings (e.g., 45degree fittings) can be used to reduce pressure drop through theself-priming adapter system 10 for faster fill rates.

FIGS. 4A, 4B, and 4C illustrate a self-priming adapter 14 according toone embodiment of the invention. The self-priming adapter 14 can includea tank 52 that creates the separation or stilling chamber 54. In oneembodiment, the tank 52 can be substantially cylindrical. Theself-priming adapter 14 can include an inlet port 56, an outlet port 58,and an air vent port 60. The self-priming adapter 14 can also includeone or more baffles 62. In one embodiment, a baffle 62 includes a firstwall 64, a second wall 66, a back wall 68, and a floor 70. In oneembodiment, the first wall 64 and the second wall 66 can be diagonalwith respect to sides of the tank 52. Including baffles 62 in theseparation chamber 54 can improve priming performance. In someembodiments, priming rates with baffles 62 can be two to three timesfaster than conventional self-priming pumps.

FIGS. 5-9 illustrate another embodiment of a self-priming adapter system10, including a pump 12, a self-priming adapter 14, a pump outlet 16, arecirculation line 18, a pump inlet 20, and an air outlet 22. Theself-priming adapter 14 can include a tank with substantiallysemi-circular sides. In some embodiments, the self-priming adapter 14can include a flapper 72. The flapper 72 in the separation chamber 54can prevent liquid from shooting through the separation chamber 54during priming and can rotate to allow liquid to flow unobstructed outof the separator chamber 54 to a filter (not shown) and/or a boom (notshown).

FIG. 9 illustrates the self-priming adapter system 10 with a check valve74 in the recirculation line 18. As shown in FIG. 9, the check valve 74can be closed when the flapper 72 is open. In one embodiment, a tankline 38 (as shown in FIG. 1) can be coupled to a tank of an agriculturalsprayer (not shown). When the tank of the agricultural sprayer becomesempty, the check valve 74 can open, allowing liquid to begin tocirculate from the separator chamber 54 to the pump inlet 20. In someembodiments, once the pump 12 is primed, pressure can increase in theseparation chamber 54. In some embodiments, a sensor (not shown) cansense the increased pressure and cause the check valve 74 to close therecirculation line 18 to the pump inlet 20. In some embodiments, thecheck valve 74 can operate at relatively low pressures (e.g., 20 PSI).In some embodiments, the check valve 74 can be a manual or electronicshut-off valve. In some embodiments, the self-priming adapter system 10can automatically control the self-priming adapter 14 circulation withan electronic valve.

FIGS. 10A-10E illustrate a self-priming adapter 14 according to oneembodiment of the invention. The self-priming adapter 14 can include atank 52 that creates a separation or stilling chamber 54. In oneembodiment, the tank 52 can include side walls having the shape of halfan octagon. The self-priming adapter 14 can include an inlet port 56, anoutlet port 58, and an air vent port 60. The self-priming adapter 14 canalso include one or more baffles 62. In one embodiment, a baffle 62includes a first wall 64, a second wall 66, and a floor 70. In someembodiments, the first wall 64 and the second wall 66 can besubstantially vertical and can extend parallel to one another along thelength of a top portion of the tank 52. In some embodiments, theself-priming adapter 14 can include suitable wall-mount brackets.

FIG. 11 illustrates another embodiment of a self-priming adapter 14,including one or more anti-vortex screens 76. The use of anti-vortexscreens 76 can improve priming smoothness. In some embodiments, theanti-vortex screens 76 are removable for cleaning. FIG. 11 illustratesone embodiment of the invention in which the separation chamber 54 ofthe self-priming adapter 14 can include two inch baffles 62 andanti-vortex screens 76 at a four foot lift height. As shown in FIG. 11,air bubbles are generally confined to an upper portion of the separationchamber 54. However, without baffles 62, air bubbles are generally freeto chum about and are easily entrained in the recirculation flow that isused for priming, resulting in surging and loss of priming capabilities.FIG. 12 illustrates a graph of priming times for a self-priming adapterhaving two inch baffles 62, while FIG. 13 illustrates a graph of primingtimes for a self-priming adapter that does not have baffles 62. Atray-like baffle 62 can be welded into the top portion of theself-priming adapter 14 to keep some of the violent air-entrainedturbulence from pulsing toward the bottom of the self-priming adapter14. Raising the sides of the baffle 62 to two inches can increase thesmoothness of the priming operation, without decreasing priming times(e.g., see FIG. 12). Adding the anti-vortex screen 76 on a bottomportion of the self-priming adapter 14 can reduce priming times by 15 to20 seconds, in some embodiments. Removing the baffle 62 can increasesurging. Without a baffle 62, the pump 12 may not be able to prime athigher RPMs due to 6 foot surges in the pump inlet 20 (e.g., see FIG.4).

In some embodiments, the self-priming adapter system 10 can be used toprovide protection from pump failure due to unexpected dry-runconditions. For example, some embodiments of the self-priming adaptersystem 10 can function automatically to prevent dry-run conditions.

The self-priming adapter system 10 can be retrofitted to an existingpump, including most manufacturers' centrifugal pump products. Theself-priming adapter system 10 can be retro-fitted to provide the sameprotection to positive displacement pumps. The self-priming adaptersystem 10 can allow existing sprayers to be retrofit and haveself-priming capabilities for on-loading or on-board loading sprayertanks.

The self-priming adapter system 10 can be used for mobile equipment thatoperates on steep grades (e.g., agricultural sprayers, DOT roadwayde-icing equipment, etc.).

The self-priming adapter system 10 can provide a protective feature forunattended equipment everywhere (e.g., industrial applications).

The self-priming adapter system 10 can allow centrifugal pumps to bemounted in tight-fitted configurations, while maintaining primingcapabilities. For example, the separator chamber 54 can be mounted in anearby remote location and a volute or standard pump housing of the pump12 can be rotated to increase the functionality of system design andmaintain the benefit of reduced pressure loss in system plumbing.

In some embodiments, including a self-priming adapter system 10 does notcompromise centrifugal pump performance due to the inefficienciespresent in a conventional self-priming chamber. In other words, the pump12 of the self-priming adapter system 10 maintains its standardperformance levels. Complex, difficult, and heavy casting patterns forconventional self-priming chambers that must be mounted vertically areno longer needed with the self-priming adapter system 10, according tosome embodiments of the invention.

One embodiment of the self-priming adapter system 10 was testedincluding a six meter (19.7 ft) priming lift height, a six meter hoselength, a 50.6 mm (two inch) suction hose diameter, and a two minutemaximum time to prime hose. A fork lift, cage, and a ten foot ladderwere used to test the self-priming adapter system 10 to specificationsthat require a 22 foot height with 50 feet of two inch hose. Increasingthe hose length can add approximately 30 to 40 seconds to overallpriming time.

In one embodiment, the pump 12 can operate at 4000-5000 RPM for goodpriming. Slower speeds yield longer priming times, but can also yieldsmoother operation. Slowing down the RPM can stop a surging effect dueto lower recirculation rates. In one embodiment, the self-primingadapter system 20 can include a 1¼ inch hose for the pump outlet 16, therecirculation line 18, and the pump inlet 20 in order to provide smoothoperation. However, different sized hose can produce different primingspeeds (e.g., faster or slower priming times) suitable for variousapplications.

FIG. 14 is a data table that includes test priming rate data for pumpsand self-priming adapter systems 10 having multiple configurations. FIG.16 illustrates a graph of flow, liquid pump pressure, and rotationalfrequency over time for a pump fitted with a self-priming adapter 14.FIG. 17 illustrates a graph of pump lift capacity data for several pumpmodels with and without self-priming adapter systems 10. Curves 80, 82,84, and 86 represent data for pumps used with a self-priming adaptersystem 10 according to some embodiments of the invention. Curves 90, 92,94, and 96 represent data for conventional pumps and conventionalself-priming pumps without the use of a self-priming adapter 14according to some embodiments of the invention.

Various features and advantages of the invention are set forth in thefollowing claims.

1. A self-priming adapter system comprising: a pump inlet receivingliquid mixed with air; a pump coupled to the pump inlet; a self-primingadapter coupled to the pump, the self-priming adapter including aseparation chamber, the separation chamber including at least one baffleto substantially separate the air from the liquid; and a recirculationline coupled to the self-priming adapter to return the liquid to thepump inlet.
 2. The self-priming adapter system of claim 1 wherein the atleast one baffle includes a first wall, a second wall, and a floormounted in a top portion of the separation chamber.
 3. The self-primingadapter system of claim 2 wherein at least one of the first wall and thesecond wall is about two inches in height.
 4. The self priming adaptersystem of claim 2 wherein the at least one baffle is mounted within theseparation chamber in order to receive liquid from an inlet port; andwherein the at least one baffle is positioned between the inlet port andan outlet port.
 5. The self-priming adapter system of claim 2 wherein atleast one of the first wall and the second wall substantially extends alength of the separation chamber.
 6. The self-priming adapter system ofclaim 1 wherein the separation chamber includes at least one anti-vortexscreen.
 7. The self-priming adapter system of claim 1 wherein theself-priming adapter includes at least one of a cylindrical tank, asemi-circular tank, and a half-octagonal tank.
 8. The self-primingadapter system of claim 1 and further comprising at least one valve toopen and close the recirculation line.
 9. The self-priming adaptersystem of claim 8 wherein the at least one valve includes a check valvepositioned in the recirculation line.
 10. The self-priming adaptersystem of claim 8 and further comprising a pressure sensor that measurespressure in the separation chamber and indicates that the pump has beenprimed; and wherein the at least one valve closes the recirculation lineafter the pressure sensor indicates the pump has been primed.
 11. Aself-priming adapter for use with a pump having a pump inlet receivingliquid mixed with air and a recirculation line, the self-priming adaptercomprising: a tank including an inlet port and an outlet port; aseparation chamber within the tank; and at least one baffle positionedwithin the separation chamber, the at least one baffle substantiallyseparating the air from the liquid.
 12. The self-priming adapter ofclaim 11 wherein the at least one baffle includes a first wall, a secondwall, and a floor mounted in a top portion of the separation chamber.13. The self-priming adapter of claim 12 wherein at least one of thefirst wall and the second wall is about two inches in height.
 14. Theself priming adapter of claim 12 wherein the at least one baffle ismounted within the separation chamber in order to receive liquid fromthe inlet port; and wherein the at least one baffle is positionedbetween the inlet port and the outlet port.
 15. The self-priming adapterof claim 2 wherein at least one of the first wall and the second wallsubstantially extends a length of the separation chamber.
 16. Theself-priming adapter of claim 11 wherein the separation chamber includesat least one anti-vortex screen.
 17. The self-priming adapter of claim11 wherein the tank is least one of a cylindrical tank, a semi-circulartank, and a half-octagonal tank.
 18. The self-priming adapter of claim11 and further comprising a pressure sensor that measures pressure inthe separation chamber and indicates that the pump has been primed. 19.A method of priming a pump, the method comprising: receiving liquidmixed with air; directing the liquid mixed with air over at least onebaffle; substantially separating the air from the liquid; and returningthe liquid to a pump inlet in order to prime the pump.
 20. The method ofclaim 19 and further comprising directing the liquid mixed with air overat least one anti-vortex screen.